In Long Term Evolution (LTE for short below) and LTE-Advanced (LTE-A for short below) systems, a base station schedules uplink/downlink data by using scheduling signaling transmitted on a physical downlink control channel (PDCCH for short), where the scheduling signaling includes a physical resource used by user equipment (UE for short below) to receive downlink data on a physical downlink shared channel (PDSCH for short below) or to send uplink data on a physical uplink shared channel (PUSCH for short below), that is, a time-frequency resource, a modulation and coding scheme and a redundancy version that are used for data transmission, and other information. In addition, data is transmitted and retransmitted in a hybrid automatic repeat request (HARQ for short below) manner in the LTE and LTE-A systems. During uplink transmission or downlink transmission, generally, only one HARQ process processes data within one transmission time interval (TTI for short below), and a same HARQ process is used for transmission and retransmission of same data, so as to obtain combined decoding gains. For downlink HARQ transmission, if scheduling signaling instructs UE to receive downlink data, the scheduling signaling also needs to include information such as an identifier of an HARQ process used by the UE to receive the data. After receiving the scheduling signaling, the UE decodes, on a notified physical resource by using the HARQ process, the downlink data according to the scheduling signaling, and feeds back a downlink data receiving status to a base station, so that the base station determines, according to the feedback, whether to perform retransmission. For uplink HARQ transmission, if scheduling signaling instructs UE to send uplink data, after receiving the scheduling signaling, the UE sends, on a notified physical resource by using an HARQ process, the uplink data according to the scheduling signaling, and receives an uplink data receiving status fed back by a base station and determines whether to perform retransmission, or receives uplink retransmission scheduling signaling sent by a base station and performs uplink retransmission.
In the LTE and LTE-A systems, one UE may simultaneously run multiple services with different quality of service (QoS) requirements, where different services correspond to different radio bearers (RB for short below), and each RB corresponds to one logical channel (LCH for short below). To improve resource utilization, before transmission of data on different RBs, multiplexing processing may be performed on the data on different RBs according to some multiplexing criteria (such as RB priority information, and a rate requirement that corresponds to the RB), that is, data on multiple different RBs that is to be transmitted is encapsulated into one media access control protocol data unit (MAC PDU for short below). During multiplexing, whether different RBs can be multiplexed needs to be further considered based on some parameters, for example, a maximum quantity of times of HARQ transmission or retransmission at a MAC layer (including a total quantity of times of transmission and retransmission). Considering that different services have different requirements on delay and reliability, different maximum quantities of times of HARQ transmission or retransmission may be used during transmission of data on different RBs, and data on RBs that has different quantities of times of HARQ transmission cannot be multiplexed in a same MAC PDU.
It can be seen that, the use of RB multiplexing to improve resource utilization in the prior art is limited by some parameters and multiplexing criteria, which causes that bandwidth resources cannot be fully used during transmission, and therefore data throughput of UE cannot be effectively ensured.